Method and apparatus for installing a flexible tubular liner

ABSTRACT

A method and an apparatus for use in installing a liner in a conduit as part of a repair procedure, the apparatus including a sealing inlet port ( 106 ) for passage of the tubular liner ( 72 ) into an enclosed container ( 52 ) where an increased pressure is maintained to move the tubular liner into the conduit ( 179 ) and to evert it as it moves along the conduit. A clamp ( 80 ) holds one end of the liner to the outlet side of an everter box ( 50 ) supported on a frame ( 18 ) that may be mounted on a trailer hitch receptable. The sealing inlet port includes a pair of lips ( 112, 114 ) to press against the opposite sides of a flattened liner. Support members ( 148, 150 ) keep the lips from being forced back out toward the outside of the pressurized everter box and control friction between the lips and the liner. Inlet and outlet fittings are provided. The apparatus is portable on a trailer hitch receiver.

This is a continuation-in-part of U.S. patent application Ser. No.09/599,820, filed Jun. 21, 2000, which issued May 21, 2002 as U.S. Pat.No. 6,390.795, entitled Apparatus for Everting a Tube.

BACKGROUND OF THE INVENTION

The present invention relates to an apparatus for everting and curing aflexible tube as a liner in the interior of a hollow tubular conduit,such as a previously existing underground sewer pipe.

One of the more successful pipe repair or rehabilitation processes whichis currently used is described in Wood, U.S. Pat. No. 4,064,211. Wood,U.S. Pat. No. 4,385,885 discloses apparatus useful in installing a lineraccording to the process described in U.S. Pat. No. 4,064,211, andbriefly mentions, but does not describe, a lip seal, used in conjunctionwith a pair of controlled rollers to feed a liner into a conduit that isto be repaired. Various other sealing devices have been disclosed foruse in connection with using fluid under pressure to evert a liner andextend it into a conduit to be repaired, as shown, for example, inAlexander, Jr., U.S. Pat. Nos. 5,597,353 and 5,942,183, Long, Jr., U.S.Pat. No. 5,358,359, Driver, et al., U.S. Pat. Nos. 5,154,936 and Re.35,944.

Other apparatus for use in installing and everting a liner, as disclosedin Long, Jr., U.S. Pat. Nos. 4,668,125 and 4,685,983, has been quitelarge, and has avoided the use of a seal to maintain pressure within aportion of an apparatus by instead using a relatively tall column ofwater to provide the necessary fluid pressure within the liner beingeverted.

Such apparatus has been undesirably unwieldy and expensive. Because ofits size, such apparatus is difficult or even dangerous to use inresidential areas where fences obstruct access to conduits in need ofrepair, and such tall support apparatus presents a risk of inadvertentcontact with electric power lines. Additionally, the weight of some suchapparatus, particularly when filled with water, makes its use difficultwherein there is no paved surface near the point of access to theconduit to be repaired.

The need to ensure stability of such tall and heavy apparatus alsopresents some concerns that it is desired to avoid.

For installation of lines in relatively small and short conduits in somecases an entire prepared liner has been stacked inside a closedcontainer, such as a special truck body, and the liner has been everteddirectly from within the truck. This method, however, presentsdifficulty in assuring that a liner is extended and everted smoothly andrequires a container of special construction to contain and withstandthe force of the pressurized fluid needed to extend and evert the linertube.

What is desired, then, is to provide a system including convenientlysmall, safe, and relatively inexpensive apparatus useful to evert andinstall a flexible tubular liner into a conduit quickly and efficiently.

BRIEF SUMMARY OF THE INVENTION

The present invention supplies an answer to the aforementioned need fora relatively small, handy, and inexpensive apparatus for use ininstalling a flexible tubular liner in a conduit, by providing anapparatus in which there is a sealing inlet port for admitting a linerin the form of a flattened flexible tube into a pressurized chamber foreverting and extending such a flexible tube into position for use torepair or line a conduit. The apparatus includes a container for holdingair or another fluid under pressure to act on the flexible tube and fromwhich the flexible tube is expelled from the pressurized chamber to beinverted by the pressure inside the chamber. The sealing inlet port isprovided in the container to allow the tubular liner to enter thecontainer in a flattened configuration without significant loss ofpressure where the tube enters the container so that the pressure of thefluid in the container can be used to evert and extend the tubular linerinto the required position within a conduit.

The sealing inlet port in one embodiment of the invention includes abase defining an elongate narrow mouth, and a pair of associated lipsextend inward for a distance from the base, facing each other. In use ofthe sealing port, fluid under pressure surrounding the lips urges thelips together and against an object such as the flattened flexible tubepassing through the sealing inlet port, to seal the inlet port yet allowthe flexible tube to slide between the lips.

In a preferred embodiment of the invention the sealing inlet port canprovide a sealing effect yet permit a rope, a lay-flat hose, a strap, orother installation hardware and fittings to slide between the lips.

In a preferred embodiment of the sealing inlet port an elongate supportmember is fastened to each of the lips to keep them in the necessarypositions and prevent them from being expressed from within thecontainer of fluid under pressure.

In one embodiment of the invention such elongate support members arespaced apart from each other, urging respective portions of the lipsapart from each other to limit friction between the lips and theflattened liner tube.

In accordance with the invention the lips provide a sealing closurearound the flattened tube being everted, but the lips are short enoughand are supported sufficiently by the support members that the frictionbetween the lips and the tube is small enough that the pressure in thecontainer urging the lips toward each other and the tube is sufficientto cause the tube to extend and be everted to a desired length.

In one embodiment of the invention a cover plate provides support forthe base to which the lips are attached, and associated shutters providea slot having an adjustable size extending through the cover plate.

In one preferred embodiment of the invention the apparatus includes aliner everter box having the sealing inlet port at its top end andincluding an outfeed opening at its bottom end, through which theflexible liner tube can proceed out from the liner everter box.

In one preferred embodiment of the invention a clamp associated with theoutfeed opening from the liner everter box includes a conical innerclamping surface surrounded by a circular outer clamping seat or rim,together with linkages holding the two together to grip an end portionof a flexible tube between the conical inner clamping face and thesurrounding clamping rim.

In one preferred embodiment of the invention a support frame holds theliner everter box in an appropriate position so that an everted linerextending from the outfeed opening can be directed conveniently to theappropriate position to enter into a conduit needing to be repaired.

In one embodiment of the invention the support frame includes adjustablelegs, adjustable wheeled struts, and a mounting arm adapted to bereceived in a trailer hitch receiver on a motor vehicle.

In one preferred embodiment of the invention the support frame andeverter box together are small and light enough to be mounted on atrailer hitch receiver on a small vehicle such as a pickup truck, to bemoved easily in restricted spaces where pipes may need repairs, as inresidential neighborhoods, without likelihood of causing contact withoverhead utility wires.

In another preferred embodiment of the invention a pair of guide rollersare mounted on the support frame above the liner everter box.

The invention also provides a system of apparatus for use in helping tocure a resin-impregnated liner in a conduit being repaired, including apressure retaining inlet fixture, or steam cap, which may be desired insome situations, to replace the liner everter after the liner has beeneverted. Such a system includes fittings permitting introduction ofsteam, water, and air at controlled temperatures, and a pressureregulating system to be connected to the opposite end of the liner.

The invention also provides a method for installing and curing in-placea resin-impregnated liner for conduits such as sewer systems, forassuring proper curing of such a liner, using steam in one embodiment toprovide required heat, and using a pig to push out condensateaccumulations in low areas.

The foregoing and other objectives, features, and advantages of theinvention will be more readily understood upon consideration of thefollowing detailed description of the invention, taken in conjunctionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is an isometric view showing a tube everter apparatus which isone embodiment of the present invention.

FIG. 2 is a semi-diagrammatic representation illustrating the manner inwhich the apparatus shown in FIG. 1 may be used to install a liner tubeinto a conduit extending from a manhole.

FIG. 3 is a front elevational view of the everter box and its outletfixture, together with upright portions of the supporting structureshown in FIG. 1.

FIG. 4 is a sectional view, taken along line 4—4 of FIG. 1, showing theoutlet fixture and liner clamp portions of the apparatus shown in FIG.1, at an enlarged scale, with a tubular liner fastened to the outletfixture of the everter box in readiness for being everted and extended.

FIG. 5 is an isometric view taken from the upper right front corner ofthe everter box shown in FIG. 1, at an enlarged scale.

FIG. 6 is an exploded isometric view showing the cover plate, theshutter assembly, and the funnel-like liner-guiding assembly of theeverter box shown in FIG. 3.

FIG. 7 is an isometric view of a base sheet assembly and associated lipsof a sealing inlet port which is one embodiment of the presentinvention, taken from the bottom, or inner, side of the base.

FIG. 8 is a sectional view, taken along line 8—8 in FIG. 5, at anenlarged scale, showing the sealing inlet port and a flattened tubularliner passing into the everter box through the sealing inlet port.

FIG. 9 is a sectional view, taken along line 9—9 of FIG. 5, showing thesealing inlet port and a flattened tubular liner passing into theeverter box through the sealing inlet port.

FIG. 10 is an exploded isometric view of the inlet seal shown in FIGS.7, 8 and 9.

FIG. 11 is an isometric view taken from the upper right front corner ofthe everter box shown in FIG. 1, at an enlarged scale, showing uprightportions of the support structure and a funnel-like liner-guidingassembly associated therewith.

FIG. 12 is an isometric view of an inlet seal assembly which is analternative embodiment of the present invention.

FIG. 13 is a sectional view, taken along line 13—13 of FIG. 11, showingthe inlet seal shown in FIG. 12 installed in the upper end of theeverter box, together with the liner-guiding assembly.

FIG. 14 is a sectional view, taken along line 14—14 of FIG. 11, showingthe inlet seal shown in FIG. 12 installed in the upper end of theeverter box, together with the liner-guiding assembly.

FIG. 15 is an exploded isometric view of the inlet seal assembly shownin FIGS. 12, 13 and 14.

FIG. 16 is an isometric view of a sealing inlet port that is anotherembodiment of the invention, shown inverted.

FIG. 17 is a section view, taken on line 17—17 of FIG. 16, showing theinlet port in its actual orientation as when in use.

FIG. 18 is a semi-diagrammatic representation of apparatus which isanother embodiment of the invention, showing its use in installing aliner tube into a subterranean conduit.

FIG. 19 is an isometric end view of a tubular liner in a foldedconfiguration.

FIG. 20 is an isometric view of the upper, or inlet, side of a basesheet assembly and accompanying sealing lips of a sealing inlet portwhich is a further embodiment of one aspect of the present invention.

FIG. 21 is an isometric view of the lower, or interior, side of the basesheet assembly and associated sealing lips shown in FIG. 20, showing thelip support assembly and the inner margins of the lips thereof.

FIG. 22 is an isometric view showing one step in the procedure ofassembling the sealing lips for the assembly shown in FIGS. 20 and 21.

FIG. 23 is an isometric exploded view of the base sheet assembly andassociated sealing lips shown in FIG. 20.

FIG. 24 is a section view of the base sheet assembly and sealing lipsshown in FIG. 20, taken along line 24—24 thereof, at an enlarged scale.

FIG. 25 is a partially schematic sectional view of a length of sewerpipe being repaired in accordance with the present invention, andshowing the use of pressure retaining fittings at the ends of the linertube being used to repair the sewer pipe.

FIG. 26 is a side view, at an enlarged scale, of an end of a liner tubewith a liner attachment nozzle attached thereto and a curing closurefitting attached to the nozzle for use during the curing of a liner tubeused to repair the length of sewer pipe shown in FIG. 25.

FIG. 27 is a diagrammatic view of a portion of a sewer pipe beingrepaired, showing a clean-out pig in use to clear the repaired sewerpipe, and showing an end fitting used to regulate the pressure of afluid contained within the repair liner.

FIG. 28 is a partially cutaway isometric view, at an enlarged scale, ofthe end fitting and pig receptacle shown in FIG. 26.

FIG. 29 is an isometric view of a length of liner tubing and an exhaustvalve manifold attached thereto by a connector port assembly.

FIG. 30 is an exploded view showing the manner of attachment of theconnector port assembly shown in FIG. 29.

FIG. 31 is a view of a pinch-off tool in use to close off a section ofliner tubing temporarily to permit installation of an end fitting.

FIG. 32 is a sectional view taken along line 31—31 of FIG. 30.

FIG. 33 is an isometric view of the top of an everter box according tothe invention equipped with a curing closure to seal the inlet slotduring curing of a liner.

FIG. 34 is a bottom plan view of the curing closure shown in FIG. 33.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring now to the drawings which form a part of the disclosureherein, an everter apparatus 16 which is one preferred embodiment of thepresent invention includes a frame 18 of metal, preferably aluminum,including a mounting arm 20 adapted to fit and be fastened in a trailerhitch receiver of a motor vehicle, for transport of the apparatus to alocation where access is available to a conduit that is to be repaired.A pair of longitudinal side members 22 are spaced apart from each otherand define an open space 24 therebetween. A pair of upright supportmembers 26, preferably of steel tubing, each extend upward from arespective one of the side members 22 and may be attached to the sidemembers 22 by fitting within respective sleeve-like sockets 28.

A pair of ground wheels 30, which may have rubber tires, are mountedrotatably on respective struts 32, each fastened to a respective one ofthe side members 22, as by being mounted adjustably and removably withina respective support sleeve 34. A respective one of a pair of horizontalextension members 36 is attached to each of the side members 22 by ahorizontal sleeve 38. Each of the sleeves 38 extends diagonally outwardfrom a respective one of the side members 22 on which it is mounted. Arespective vertical support leg 40 is adjustably held within a mountingsleeve 42 on each of the horizontal extension members 36. The verticalsupport legs 40 may be adjusted by locking pins and corresponding holes,to rest on the ground and support the side members 22 so that the frame18 is suitably supported where a flexible tube is to be installed, suchas, for example, a location where the open space 24 is located above amanhole, as illustrated in FIG. 1.

The entire apparatus, in a preferred embodiment, has a weight of lessthan 400 pounds, so it can be transported by being mounted in a trailerhitch receiver of suitable strength with the struts 32, extensionmembers 36, and legs 40 retracted or removed.

Located between the upright support members 26 is a liner everter box 50which, for light weight, is manufactured of aluminum plates weldedtogether to form a generally rectangular container 52 including a flange54 at its top end and having a generally tubular outfeed fixture 56mounted on its bottom end. The everter box 50 is attached to the uprightsupport members 26 by a pair of mounting sleeves 58 attached to oppositesides of the container 52 and fitting loosely about the upright supportmembers 26. Horizontal mounting pins 60 extend through respectivecoaxial bores defined in each mounting sleeve 58 and corresponding boresin the upright support members 26, allowing the liner everter box 50 topivot about an axis defined by the mounting pins 60, through an angle 62with respect to the upright support members 26.

A moveable subframe 64 is attached removably to the upright supportmembers 26 a convenient distance above the mounting sleeves 58 andsupports a first generally cylindrical roller 68 for rotation about agenerally horizontal axis that extends parallel with the axis defined bythe mounting pins 60. The roller 68 has a pair of flanges 70 eachextending radially from the surface of the roller 68 at a respective oneof its opposite ends. The roller 68 is mounted in a fixed location withrespect to the subframe 64.

A second roller 74 is also carried on the moveable subframe 64, to whichit is attached by a pair of similar parallel swing arms 76 between whicha roller shaft 78 extends. The second roller 74 is similar in itsdiameter to the size of the roller 68, but is slightly shorter inlength, so that the second roller 74 fits between the flanges 70,allowing the peripheral surface of the second roller 74 to move intocontact with the peripheral surface of the roller 68. Ordinarily, duringuse of the everter apparatus 16, a prepared liner tube 72 to beinstalled in a conduit being repaired extends over the first roller 68and thence down through a liner passage space established between thefirst roller 68 and the second roller 74 merely by moving the secondroller 74. The weight of the second roller 74, acting through the swingarms 76, urges the second roller 74 against such a liner tube 72,holding it neatly and appropriately in place along the peripheralsurface of the first roller 68.

The entire apparatus has a height, in a preferred embodiment, of no morethan about 10 feet so that it is convenient to use and does not presenta risk of encountering normal overhead utility lines.

Attached to the outfeed fixture 56 at the bottom end of the container 52is a liner attachment clamp 80, held in place by a fastening collar 82,with a gasket 83 included between the fixture 56 and the linerattachment clamp 80 to provide a seal to retain pressure. The attachmentclamp 80 may be constructed in various sizes and is used in a sizeparticular to the size of the liner tube 72 to be installed, to retainthe first, or near end 92 of the liner tube 72 and create a tight sealbetween the liner tube 72 and the interior of the container 52. Pressurecan then be applied to the fluid within the interior of the container 52to evert the liner tube 72 and force it to extend into position withinthe conduit which is to be repaired using the everter apparatus 16. Tothat end, the attachment clamp 80 includes an upper sleeve portion 84,shown in section view in FIG. 4, which fits snugly within the lower endof the outfeed fixture 56. A radially outwardly extending flange of theupper sleeve portion 84 fits against the lower end of the outfeedfixture 56, and radially inwardly extending flanges of the collar 82hold the upper sleeve 84 together with the lower end of the outfeedfixture.

An outer clamping seat 86 is located at the bottom end of the uppersleeve 84 and extends radially inward in the form of a rim, defining acircular opening, in the embodiment shown.

An inner tubular portion 90 is frusto-conical and has an open upper endthat is smaller than its lower end and also smaller than the opening.The upper end is also small enough to fit a short distance into the opennear end 92 of the liner 72.

At least two ears 94 extend radially outward from the exterior of theinner tubular portion of the attachment clamp 80, and correspondinglylocated clamp lever arms 96 are mounted on the upper sleeve portion 84.Each clamp lever arm 96 carries a U-shaped bail 98 of adjustable lengthas well as a latching hook 100, so that when the bail 98 engages arespective gear 94 and the clamp lever arm 96 is raised, the latchinghook 100 can engage a corresponding shoulder on a mounting base 102 onthe outside of the upper sleeve 84.

With the smaller end of the inner tubular portion of the clamp 80extending a small distance into the near end 92 of the liner 72 theclamp lever arms 96 are raised and latched, to grip the near end 92 ofthe liner between a clamping seat portion 99 of the inner tubularportion 90 and the outer clamping rim 86, as shown in FIG. 4, withsufficient force to prevent the near end 92 from becoming dislodgedduring operation of the everter apparatus 16. The liner 72, folding backinside the portion gripped by the clamp 80, extends downward through theinterior of the inner tubular portion 90, thus being everted as more ofthe length of the liner 72 passes through the inner tubular portion 90of the attachment clamp 80 in the direction indicated by the arrow 104.

At the upper end of the everter 50, the liner 72 extends downward fromthe space between the rollers 68 and 70 and moves into the interior ofthe container 52 through a sealing inlet port 106 in response toelevated fluid pressure within the container 52 acting on the surfaces108 of the liner 72 to evert and extend it through the outfeed fixture56. The liner 72 is typically of one or more layers of felt, usually aneedled felt of polyester fibers, 3 mm–6 mm thick, sewn into the form ofa tube, with a layer 110 of a flexible polymeric plastic material suchas a 10- or 15-mil polyurethane film bonded to the felt, usually byspraying the polyurethane onto the felt in a liquid state and allowingit to fuse onto and around the fibers in the outermost part of the layerof felt. Shortly prior to installation of a liner 72 the felt is usuallyimpregnated with a quantity of an uncured resin which is containedwithin the liner 72 and within the plastic film layer 110 on whosesurfaces 108 pressure acts within the container 52.

In one embodiment of the present invention, the sealing port 106includes a pair of lips 112, 114, shown in FIGS. 7, 8, 9 and 10, whichin one preferred embodiment of the invention extend from a base 116which has an outer face 118 and an opposite inner face 120. The base 116is in the form of a base sheet assembly of multilayered construction andis attached to the flange 54 at the upper end of the container 52 by acover plate 122 and several fasteners such as bolts 124 threaded intothe flange 54. The cover plate 122 supports the base 116 when fluidpressure within the interior of the container 52 is increased withrespect to the ambient air pressure surrounding the everter apparatus16. The cover plate 122 defines a slot 125 of ample size including longparallel sides interconnected by short ends, through which the flattenedliner 72 passes into the container 52.

The base 116 defines a long, narrow inlet mouth 126 which has a length127 and a pair of opposite sides 128 generally parallel with each otherand spaced apart by a distance 130 that is sufficient to permit passageof the flattened liner 72.

The lips 112, 114 are included in a short tubular piece of strongflexible sheet material such as the felt of which the liner tubes aretypically manufactured, and which has an attached airtight layer 110 offlexible polymeric plastic material such as an intimately adhered 10–15mil polyurethane film. The tubular portion defining the lips 112, 114may be made by sewing in place a small connecting piece of felt, asshown in FIGS. 9 and 10. The tubular portion including the lips 112, 114is attached to the base 116, as by sewing, with the attached end 131 ofthe tube opened as shown best in FIG. 10. The base 116 preferablyincludes a pair of layers 132, 134 of such felt with an adhered film 110of a flexible plastic material. The base 116 may be assembled with theplastic film 110 of each layer facing toward the plastic film of theother of those two layers. Thus the polyurethane layer 110 of the layer134 is uppermost, while the polyurethane layer 110 of the layer 132faces downward. The opened end 131 of the tube, including the lips 112,114, is sandwiched between the layers 132 and 134 as seen best in FIGS.8 and 9, and the opened end portion 131 is preferably sewn to the layer134, preferably with two or three lines of stitches, as indicated inFIG. 10, with the tube extending down through the opening in the layer134.

A layer 136 of a rubberlike material, such as a ⅛-inch-thick siliconerubber, is located in contact with the lower layer 134 of felt andplastic, and a bottom sheet 138 of a polymeric plastic able to withstandtemperatures at least as high as about 250°–300° F., such as a sheet ofPTFE (polytetrafluoroethylene) 1/32 inch thick, is located in contactwith the layer 136 of rubber, forming the inner face 120 of the base116. PTFE is desirable, because of its ability to withstand thetemperatures which may result from the introduction of steam into theliner receiver 50 to heat the uncured resin with which the liner 72 isimpregnated, in order to cause it to commence curing once it has beeninstalled. A thicker layer 140 of plastic, such as PTFE 1/16–⅛ inchthick, is located in contact with the upper layer 132 of felt andplastic and includes the outer face 118 of the base 116. All of thelayers may then be sewn together.

The lips 112, 114 extend generally parallel with each other away fromthe base 116 in an inward direction, toward the interior of thecontainer 52, for a distance 142, which may also be referred to as adepth of each lip 112, 114. The distance 142 is preferably in the rangeof 1 to 6 inches, depending on the size of the liner 72, and is, forexample, about 3¼ inches, when the distance 130 between the oppositesides 128 of the mouth 126 is 1½ inches, so that there is ample area inthe lips 112, 114 to be acted upon by the fluid contained under pressurewithin the container 52, to urge the lips 112, 114 toward each other sothat their mutually confronting sealing surfaces 144, 146 are forced tobear against the surfaces 108 of the liner tube 72 where it extendsthrough the sealing port 106.

The lips 112, 114 are supported by elongate resiliently flexiblesupporting members 148, 150 extending along the exterior surfaces 152,154 of the lips 112, 114. Each of the support members 148, 150 may be asteel strap 0.5 inch-1.375 inch wide and 0.075–1.125 inch thick, forexample, and is attached to the respective lip 112 or 114 by extendingthrough a tube defined by a strip 156 of flexible material, preferablythe same sort of felt material of which the lips 112, 114 are made. Thestrips 156 are attached preferably by being stitched along theirmargins, leaving a space wide enough to admit the support member 148 or150.

Each support member 148, 150 has a length 160 somewhat greater than thelength of the mouth 126, and a fastener such as a bolt and nutcombination 162 extending through holes 164 interconnects the supportmembers 148, 150 with each other loosely, to establish a maximumseparation between them. The support members 148, 150 thus prevent thelips 112, 114 from being forced out through the mouth 126 when thecontainer 52 is pressurized.

In this embodiment of the invention a helical compression spring 165 ispreferably located on each bolt 162 between the support members 148 and150, urging them apart from each other toward the position of maximumseparation permitted by the bolts 162 or equivalent fasteners. Thesupport members 148, 150 thus serve to urge the lips 112, 114 apart fromeach other, counteracting a portion of the force of fluid under pressurewithin the container 52 to reduce friction acting on the surface of theliner 72 as it passes into the interior of the liner everter box 50, butwith a small enough force that the lips 112, 114 are not prevented fromforming a seal. Thus the support members 148, 150 prevent the lips 112,114 from being forced out through the mouth 126 yet the springs 165permit the sealing surfaces of the lips 144, 146 to be pressed intocontact with each other and against the surfaces 108 of the liner 72being everted.

The sealing surfaces 144 and 146 are preferably lubricated to facilitatepassage of the liner 72 through the sealing inlet port 106, byimpregnating the felt of the lips 112, 114 with a lubricant such as asilicone lubricant having a kinematic viscosity of 100,000 centistokes,available from Dow Corning as its Series 200 silicone lubricant, forexample.

A liner such as the liner 72 is typically prepared by impregnating thefelt layers with the appropriate uncured thermosetting resin, with thepolymeric plastic film layer outermost, containing the resin. The lineris then placed in a refrigerated container to prevent the resin fromcuring until the liner has been properly installed within a conduit tobe repaired. Since the length of a liner may be up to several hundredfeet, small amounts of air contained within a liner may accumulate andform a bubble within a liner 72 outside the liner everter box 50.Because of the cooperation of the rollers 68 and 74, such a bubble willusually remain between the rollers and the container in which the lineris stored prior to installation. To provide additional guiding supportto keep the liner 72 properly aligned and flattened as it enters theliner everter 50, however, a pair of convergent guiding members 166 maybe provided on the outside of the cover plate 122. The guiding members166 may preferably be made of a low-friction sheet polymeric plasticmaterial thick enough to provide ample support considering the size ofthe liner 72, and preferably may be of PTFE 1/16 inch thick, and thusthey also act as slip sheets. They are generally fan-shaped, withmargins 168 interconnected as by being sewn together to form a flattenedfunnel leading into the slot 125 defined in the cover plate 122. Thefunnel formed by the guiding members 166 squeezes the liner 72, shouldit contain a significant bubble, urging the liner 72 into its requiredflattened form so that it can pass through the sealing inlet port 106.The guiding members 166 may extend only a short distance into the mouth126, or in another embodiment of the invention may extend further intothe cavity defined within the interior of the container 52.

Preferably, an adjustable slot filler assembly 169 is provided to adjustthe size of the slot 125 extending through the cover plate 122. Such afiller assembly preferably includes a pair of opposite shutters 170 thatare similar to each other. Each has a flat base portion 172 extendingalong the inner surface of the cover plate 122, and an upstanding wallportion that stiffens the shutter 170 and extends upward into the slot125 to narrow it to approximate more closely the size of a flattenedliner 72. Two opposite flat end plates 176 extend transversely withrespect to the shutters 170 and may be moved toward or away from eachother adjacent to the ends of the slot 125 to reduce the length of theslot 125 similarly to more closely approach the size of the flattenedliner tube 72 where it enters into the liner receiver 50 through thesealing port 106. The shutters 170 and end plates 176 fit snugly betweenthe base portion 116 and the cover plate 122, so that once they areadjusted to the size of a particular liner 72 they will remain in thedesired position, particularly when the interior of the container 52 issubjected to increased fluid pressure which will urge the base 116 moretightly into contact against the end plates 176, shutters 170, and coverplate 122.

When the first or near end 92 of the liner 72 is held by the clamp 80 asshown in FIGS. 1–4, with the flattened liner 72 extending into theeverter box 50 through the sealing inlet port 106, increasing the fluidpressure, as by introducing compressed air into the interior of theliner everter box 50, will urge the liner 72 out from the container 52through the outfeed fixture 56 and the appropriately installedattachment clamp 80, with the liner 72 being everted at its furthestextended portion as shown at 178 in FIGS. 2, 3 and 4. Fluid pressurewithin the interior of the liner everter 50 in excess of ambient airpressure will also urge the lips 112 and 114 toward each other and intocontact with the portion of the liner 72 extending into the linereverter box 50 through the sealing port 106, preventing escape of thecompressed air or other fluid under pressure from inside the linereverter box 50, yet permitting the liner 72 to slip between the lips 112and 114 on its way into the everter box 50 and toward the outfeedfixture 56 at the bottom of the container 52. Preferably, as shown inFIG. 2, where a conduit 179 to be repaired extends away from one side ofa manhole 180 whose base is wider than the opening at ground level, theliner 72 will extend at an angle of inclination with respect to thevertical, and the liner receiver 50 is able to tilt somewhat toaccommodate that path of the everted liner 72.

Once the entire length of the liner 72 has passed through the sealingport 106 into the liner everter box 50, a tail rope 182 attached to thetail, or far end of the liner 72 can also be allowed to pass into theliner everter 50 through the sealing inlet port 106, which will alsocreate a sealing closure around the tail rope 182. Tension can bemaintained in the tail rope to control the speed at which the liner 72is carried along the interior of the conduit 179 as it continues to beeverted within the conduit. Such control is desirable to assure that theliner 72 is subjected to sufficient pressure while eversion within theconduit is allowed to take place. The tail rope 182 may be extendedaround one of the rollers 68 and 74 and allowed to slip at the desiredspeed around a cleat 184 located on the exterior of the liner receiverbox.

Once the liner 72 has been everted completely to the far end of thesection of conduit 179 being repaired, the far end of the liner 72 canbe sealed and contained as necessary to maintain pressure within theliner 72 and permit heat to be provided to the interior of the liner 72in the conduit 179 to commence the curing of the resin. Depending on howheat is intended to be applied to the interior of the conduit with theeverted liner in place, it may also be desirable to utilize the tailrope 182 to pull a lay-flat hose 186 toward the far end of the evertedliner 72 so that hot water, steam, or heated air can be carried throughthe lay-flat hose 186 to the far end of the section of conduit beingrepaired. Such a lay-flat hose 186 may also be moved through the sealingport 106 together with the tail rope 182.

Referring now to FIGS. 11–15, a sealing port 190 is of slightlydifferent construction from that of the previously described sealingport 106. The sealing port 190 is used by being installed in the samemanner as the sealing inlet port 106, between the flanges 54 and thecover plate 122, shutters 170 and end plates 176, and is also similarlysupported by attachment to the flange 54 using the bolts 162. A baseportion 192 is of multilayered construction including a top sheet 194 offelt with an adhered plastic film as described above. A slot 196 definedin the top sheet 194 is diamond-shaped, wider at midlength than at itsends, and may include circular stress-relief portions at each end and inthe middle to make tearing of the material less likely. A bottom sheet198 of elastic rubber-like material such as a silicone rubber materialabout ⅛ inch thick includes a slit 200 also having stress relievingcircular openings at its ends. A lower intermediate layer 202 includes apair of separate sheets 202 a and 202 b, each located on a respectiveside of the slit 200 and each including a respective lip portion 204 a,204 b, extending downward through the slit 200. The separate parts 202 aand 202 b of the lower intermediate layer are of a flexible, strong, andfairly thick material such as the previously described felt materialcommonly used as the material of the tubular liners 72 and whichincludes an adhered layer of a polymeric plastic material such as 10–15mil polyurethane film on the upper side of the lower intermediate sheetpal. An upper intermediate sheet 206 is of a low-friction polymericplastic material such as PTFE in two parts 206 a and 206 b, shapedsimilarly to the parts 202 a and 202 b, and may be 1/32 inch to 1/16inch thick. Lip portions 205 a and 205 b are included and extend thoughthe slit 200 overlying the lip portions 204 a, 204 b. The top sheet 194is also of such felt with an attached film of polymeric plastic. Theseveral layers of the base portion 192 are stitched together, and theends 207 of the lips 204 a, 204 b, 205 a, 205 b, are also stitchedtogether, keeping the lips aligned with each other, and the lips arealso supported and resiliently urged together by the bottom sheet 198,as seen best in FIG. 14.

A pair of fan-shaped guiding members 208 of low-friction plastic sheetmaterial such as PTFE material, similar to the guiding members 166,extend above the cover plate 122 and also extend into the container 52between the lip portions 204 a and 204 b, preferably extending into theinterior of the container 52 to a distance 210 extending beyond thebottom margins of the lips 204 a, 204 b, as shown in FIG. 14.

Instead of assembling the parts of the sealing inlet port 190 as justdescribed, it would also be possible to mold in combination a base and apair of sealing lips of a suitable rubber or rubber-like plasticmaterial of appropriate flexibility and hardness to be pressed sealinglyagainst a liner tube 72 and an associated tail rope 182 and lay-flathose 186.

Various connector fittings are provided on the walls of the linereverter box 50 to accept hoses or pipes as necessary to delivercompressed air, steam, or water to the interior of the container 52 tofill the liner 72 and thus force it to evert itself and extend into aconduit being repaired using the apparatus 16 of the invention. Apressure gauge 212 is also provided, preferably protected by anappropriate shield to prevent damage during use of the apparatus. Itwill be understood that various valves will also be necessary to controlthe amount of air, steam, or water delivered to the liner receiver 50.

Ordinarily, the pressure required within the container 52 to extend andevert a liner 72 for a conduit being repaired with a nominal insidediameter of eight inches, using a double thickness felt liner, will bewithin a range of about 15 psi to 30 psi, preferably being about 10 psi.Since the pressure is fairly low, then, the lips 112, 114 of the sealinginlet port 106 must be flexible enough to conform to the liner 72 as itpasses through the port into the interior of the liner everter 50, toprevent excessive leakage. It will be understood, however, that someleakage will still be acceptable and is unavoidable.

Referring now to FIGS. 16 and 17, a sealing inlet port 220 is shown inFIG. 16 inverted from its normal orientation at the top of a linereverter container 52. The sealing inlet port 220 includes a base portion222 which may be of sheet aluminum, shaped and perforated to fit atopthe flange 54, together with an appropriate gasket (not shown). It willbe apparent that with appropriate spacers and gaskets (not shown), thecover plate 122 and the shutter assembly 169 can be used together withthe sealing port 220, as could the guiding members 166.

Extending from the base plate 222 is a support tube 224 which may be ofa modified oval shape and which is welded to the base plate 222 alongthe margin of a similarly-shaped mouth 226. Fitted snugly around thesupport tube 224 is a sleeve 228 of flexible sheet material, which maybe material similar to that of which the liner 72 is constructed. A basemargin 230 of the sleeve is fastened to the support tube 224, as by asuitably tensioned hose clamp 232. At the opposite end of the sleeve 228a pair of flaps 234 and 236 are folded back along the outside of thesleeve 228 and stitched to the material of the sleeve to form a pair oftubes 238, 240, each extending alongside a respective lip 242, 244.Overlying margins 246 of the material of which the sleeve 228 is mademay be sewn together to form the sleeve after the flaps 234, 236 havebeen sewn to form the tubes 238, 240.

Supporting members 248, 250 extend respectively through the tubes 238and 240. The supporting members 248 and 250 may be similar to thesupporting members 148, 150 described above, and are interconnected witheach other similarly by fasteners such as bolt-and-nut combinations 252extending through respective bores defined in the supporting members248, 250. Compression springs 254 are fitted around the bolts 252 andserve to urge the supporting members apart from each other in the mannerpreviously described to prevent the lips 242, 244 from pressing againsta liner tube with too much pressure and thereby causing excessivefriction.

As shown in FIG. 18, in one embodiment of the invention a flexibletubular conduit 260 is attached to the outfeed fixture 56 by a coupling262, and the attachment clamp 80 is attached to the opposite end of theflexible conduit 260 by a coupling 264, so that the rear end 92 of theliner 72 may be held by the attachment clamp 80 at a location moreimmediately adjacent to the conduit 179 which is to be repaired byinsertion of the liner 72. The flexible conduit 260 may be of anyflexible substantially airtight material capable of withstanding thepressures and temperatures utilized in extending and everting the liner72, such as material similar to that of which the liner 72 may beconstructed, that is, strong felt with a coating of polyurethane to makethe material airtight. Use of the flexible conduit 260 between the linereverter container 52 and the open end of the conduit 179 saves theexpense of preparation of a length of liner material equal to the lengthof the conduit 260 and saves the expense of treating such a section ofliner material with the required resin. Utilization of the liner everterbox 50 with the flexible conduit 260 attached is the same as with thenear end 92 attached to the attachment clamp 80 immediately adjacent tothe outfeed fixture 56, except that the near end 92 of the liner 72first needs to be pulled through the flexible conduit 260 and thenattached to the attachment clamp 80.

When utilizing the apparatus of the present invention for installationof a liner tube 72 for a conduit being repaired which is of a smallerinside diameter, such as 6–10 inches, the liner tube 72 may be foldedflat as shown in FIGS. 1–4. Instead, and particularly for repair oflarger conduits, such as 12 inches and larger in diameter, utilizing theapparatus of the present invention, a liner 272 may be folded into a “U”or flattened “C” configuration as shown in FIG. 19. This configurationpresents significantly less outer surface upon which the lips of thesealing inlet port 106 or 190 or 220 are brought to bear frictionally bythe pressure of fluid contained within the liner everter container 52 sothat the liner 272, exposes less surface to the lips and can slidethrough the sealing inlet port with less friction. The liner 272 canthus be extended and everted without having to increase the pressure onthe fluid within the liner everter container 52 more than is desirable.

The apparatus described enables a liner 72 or 272 to be extended andeverted by use of air pressure within the liner everter container andthe portions of a liner which have been extended and everted, as will bedesirable in most cases. In the installation of larger sizes of linersinto conduits being repaired it may also be desirable to use waterwithin the liner during installation to reduce friction between thesurfaces of the moving portion of the liner against the already-evertedportions of the liner within the conduit 179.

A further alternative embodiment of the sealing inlet port is shown inFIGS. 20, 21, 22, 23 and 24, where a sealing inlet port 280 for use inan everter box such as the liner everter box 50 shown in FIGS. 3 and 5includes a base sheet assembly 282 supporting a pair of lips 284, 286,which extend through a mouth 288 defined by the base sheet assembly.

The base sheet assembly 282 includes a pair of layers of material suchas the polyurethane-coated polyester felt material of which the linertube 72 is made, although, if desired, the base sheet assembly may be ofother strong, somewhat flexible sheet material which is substantiallygastight and able to withstand elevated temperatures and pressures. Anupper layer 290 and a lower layer 292 are preferably oriented with thepolyurethane coated sides of the felt material facing apart from eachother.

The lips 284, 286 for the sealing inlet port 280 shown in FIGS. 20–24are intended to contain the air or other gas under pressure used toevert a tubular liner 72 to repair a conduit which is smaller than themaximum size liner 72 that the everter box 50 is capable of handling,and so the mouth 288 has a length 298 that is shorter than the length ofthe inlet opening or slot 125 in the cover plate 122 of the everter box50 (FIG. 5). To reinforce the parts of the base sheet assembly 282 thatclose parts of the slot 125 beyond the mouth 288, a pair of sheet metalsupport plates 300 are located between the upper and lower layers 290,292, as seen best in FIGS. 20 and 21. For a similar sealing port for atubular liner 72 of the maximum size for the everter box 50 the supportplates 300 are unnecessary.

The lips 284, 286 are preferably constructed from a strong flexiblesheet 303 of material such as the same sort of felt with a coating ofpolyurethane on one side, although other materials might also suffice.An overlying sheet 301 of a tough, flexible, low-friction material suchas polyurethane having a thickness of 20 mils, for example, isadhesively attached on the polyurethane coated side of the felt 303 asshown in FIG. 22. The felt sheet 303 and the overlying polyurethane 301may then be rolled inward as indicated by the arrows 305 and formed intoa flattened tube with the polyurethane sheet 301 facing inward, as maybe seen best in FIGS. 21, 23, and 24. Edges of the felt material 303 areattached to each other adhesively at 302, and a portion of the sheet 301of polyurethane is overlapped and adhesively fastened. The polyurethanecoating and the sheet 301 are thus the inner faces of the lips 284, 186.A strip 307 of polyurethane is also adhered to the polyurethane sheet301 and to the polyurethane coating of the felt 303, along the buttjoint 302.

Alternatively, the connected sheets 303 and 301 may be formed into atube with the bare felt side of the sheet 303 facing inward so that alubricant may be absorbed in the felt and act on a liner 72 passingthrough the sealing port 280.

Two rectangular pieces 304, preferably of similar coated felt material,are then sewn to the sheet material 303 along median seams 308 and loweredge seams 310, as may be seen best in FIG. 24, on the exterior side ofthe flattened tube. One of the pieces 304 bridges the butt joint 302.Enough material of the pieces 304 is provided between the median seam308 and the lower edge seam 310 to form outwardly protruding tubes 312,each of which is to hold one of a pair of supporting members 314alongside the materials of the flattened tube, as shown in FIGS. 21 and24. The supporting members 314 are preferably metal bars, although othersuitably strong material substantially stiffer than the felt could alsobe used.

The upper portion of the felt material 303 of the flattened tube formingthe lips 284 and 286 is cut and flared outward and sewn to the upperlayer 290 of the base sheet assembly in a pair of upper seams 306 spacedoutwardly apart from each side of the mouth 288. Short seams 316 areused to sew the tabs 318 thus formed to the upper layer 290, and asuitable sealant such as a silicone caulking material may be installedalong the margin of the mouth 288 in the upper layer 290 of the baseassembly. Thereafter the lower base layer 292 is placed over theassembled parts, the support plates 300 are put in place, and theuncovered felt surfaces of the layers 290, 292, are fastened to eachother using an adhesive or by flame bonding, with the central portionsof the upper and lower sheets 290, 292 flexed downwardly as shown bestin FIG. 24. A seam 320 is sewn through the upper and lower layers 290,292 of the base sheet assembly, the material of the flattened tubeforming the lips 284, 286, and the pieces 304, along the upper margin ofeach lip 284, 286, as shown in FIG. 24. Peripheral seams 294 and 296 arethen sewn. Bolt holes 322 are cut and the layers 290, 292 are trimmed tosize. For less friction during use, a patch 324 of thin PTFE sheetmaterial may be fastened by an adhesive to each of the confronting facesof the lips 284, 286, as seen best in FIGS. 20, 23, and 24.

Thereafter, the supporting members 314, or bars, are inserted throughthe tubes 312 on each of the lips 284, 286 and fasteners such as thethreaded rods or stud bolts 326 are placed through the holes 328 locatednear each end of each of the bars, with two nuts 330 threaded onto thestuds 326 between the bars 314. A suitable radially-extending spacer,such as a large fender washer 332, is placed on each end of each stud326 and followed by another nut 334. The nuts 330 and 334 are tightenedon each side of the bar and spacer combination to adjustably establishthe separation distance 336 between the two bars 314 (FIG. 24). A singlespacer (not shown) or a spring such as the springs 165 might also beused, but the nuts 330, 334 provide both adjustability and a fixedspacing 336. The supporting members 314 are preferably kept parallel andspaced apart from each other, at a separation distance 336 small enoughto permit the confronting inner faces of the lips 284, 286, andparticularly the lower end polyurethane sheet flexible skirt portion 338of each of the lips, to be pressed against the surfaces of a liner tube72 being everted through the sealing port assembly 280.

The spacers 332 keep the bars 314 located in a position spaced farenough inwardly beneath the lower layer 292 of sheet material of thebase sheet assembly 282. This helps keep the central portion of the basesheet assembly 282, adjacent the mouth 288, stretched downward in ashallow V configuration as shown best in FIG. 24, helping to guide thetubular liner 72 toward and through the mouth 288 and lips 284 and 286,particularly should a bubble develop in the flattened liner tube outsidethe everter box 50. The spacers 332 and bars 314 also prevent pressurewithin the everter box 50 from forcing the lips 284, 286 to foldupwardly and out through the mouth 288. As the bars 314 extend beyondthe length 298 of the mouth 288 they cannot pass through the mouth, andthey keep the lips 284, 286 on the inner side of the base sheet assembly282. Each tube 312 is shorter than the lip 284 or 286 to which it isattached, so that the interconnected ends of the lips are free to flexto provide an effective seal against the surface of the fold in theflattened liner 72.

The spacing between the bars 314 is preferably adjusted to a distanceslightly greater, for example, 20 mm more, than the pinch roller gapsetting used in impregnating the liner material with uncured resin. Thisspacing 336 should be tightened if the lips 284, 286 tend to flutter orthe lower skirt portion 338 tends to be reversed and blown outwardalongside the liner tube 72 being drawn into the everter box through thesealing inlet port 280. If there appears to be too much friction theseparation distance 336 should be increased.

If desired, the lower or skirt portion 338 of the lips 284, 286 may betrimmed shorter to reduce the amount of frictional drag, although thatresults in less efficient sealing. Alternatively, the central part ofthe skirt portion of each lip may be cut in a curved shape as indicatedin broken line at 340 in FIG. 21 so that the interconnecting endportions provide a better seal along the fold on each side of theflattened liner tube while friction is reduced somewhat.

While the sheets 324 of PTFE are provided to reduce friction, a spraynozzle should also be used continually during eversion of a liner tube,to lubricate the surfaces of the liner and the lips 284, 286 in order topromote efficient eversion of a liner tube 72.

Referring now to FIGS. 25 and 26, once a tubular liner 72 has beeneverted into a segment of conduit 179 being repaired, it is necessary tocure the plastic resin or other bonding and strengthening material withwhich the liner wall material is impregnated before installation. Whileit is possible to leave the liner 72 connected to the everter apparatus16 as shown in FIG. 1 during the process of curing the liner in place,in many cases it is preferred to disconnect the liner 72 from theeverter so that the everter apparatus 16 can be moved to another sitefor installation of another liner while the first one cures. For thatreason, a pressure retaining inlet, or “A” end, fitting 342, which couldalso be called a pressure cap or steam cap, is provided and mates with aliner attachment hookup nozzle 344 which can be connected to the outletopening of the everter. The inlet or “A” end fitting mates sealinglywith the liner attachment hookup nozzle 344, as by a clampingarrangement in which a rim 346 of the liner attachment hookup nozzle 344faces a rim 348 of the “A” end fitting 342, with a suitable gasketarrangement provided, while a clamp 350 holds the two items together byencircling the rims 346, 348. Other clamp arrangements could also beused, such as one similar to that described above in connection with theattachment clamp 80. The liner attachment hookup nozzle 344 of theappropriate size includes an outlet portion that fits snugly within anend of a section of tubular liner 72 which is then attached to thenozzle 344 securely by the use of a band-type clamp 352. Use of the “A”end fitting as just described and as shown in FIGS. 25 and 26 makes theeverter apparatus 16 available quickly for use at another site while theliner 72 is curing.

A pair of inlet ports 354 and 356 are provided in the “A” end fitting orcover 342 and include fittings to which hoses or other suitable conduitsmay be connected. An air manifold may be connected between an aircompressor 360 and the port 354 through a conduit 358 and a cutoff valve362, to provide a vigorous flow of air through the interior of the linertube 72, to keep it inflated and thus tightly pressed against theinterior of the conduit 179 being repaired. If necessary, the valve 362can be used to throttle the flow of air to the port 354.

Steam or hot water may be provided through the other port 356, in orderto raise the temperature within the newly everted liner tubing 72 tostart and maintain the chemical reactions necessary to cure athermosetting resin used to impregnate the felt material of the typicaltubular lining 72 used for this type of repair of a conduit 179.Alternatively, steam or heated air could be fed through the port 354together with the flow of air from the compressor 360 and a pressure ortemperature gauge could be installed in the port 356.

At its opposite, or “B” end, the newly installed tubular liner 72 isclosed, as shown in FIGS. 1 and 25. A conduit 364 such as an exhausthose equipped with a cutoff valve 366 is connected to the liner at thefar, or “B” end 368, in a sealing manner in order to maintain pressurewithin the liner 72 while it is curing. This may be accomplished simplyby opening the end of the liner tube and clamping it around a length ofpipe (not shown) large enough to carry the desired volume of air toassure adequate flow in the liner for curing, and the hose is connectedto the pipe.

Preferably, the conduit 364 is connected to temperature and pressuregauges 370, 372, so that the temperature and pressure can be monitoredand controlled at the far, or “B” end of the conduit being repaired. Thepressure can be controlled by use of a valve 374 to relieve excesspressure. Such a valve 374 may be operated manually, or it may be apressure regulating valve adjusted to maintain automatically a desiredpressure at the “B” end, about 10 psig, for example, to ensure flow of afluid curing agent such as hot air or steam throughout the segment ofconduit 179 being repaired. In response to the temperature being toohigh or low, the amount of hot air or steam admitted through the “A” endport 356 can be adjusted as required. A muffler 375 may be provided.

As shown in FIGS. 27 and 28, a preferred “B” end or pressure retainingoutlet fitting 376 according to the present invention is generallycylindrical and may be made of sheet steel or thin wall pipe with adiameter 378 similar to the diameter of the tubular lining 72 with whichit is to be utilized. A first end 380 of the “B” end fitting is open,and the end of the tubular liner 72 can be fitted over it and fastenedby a suitable band-type clamp 382. The outlet fitting 376 includes acylindrical cavity 384 whose inside diameter is similar to the insidediameter of the liner. The cavity has a length 386 which is great enoughto receive at least one and preferably more than one clean-out pig 388in the second 390, or far end of the fitting, while an exhaust port 392is located closer to the first, or open end 380 of the fitting.

A drain port 394 is located in the far or second end 390 of the fitting376. The drain port 394 is provided with a valve 396 which may be usedto drain hot water used to cure a liner after installation, or to draincondensate from a liner in which steam has been used to provide the heatnecessary to promote curing of the liner, but the valve otherwise wouldusually be kept closed.

A suitable valve 366 is associated closely with the exhaust port 392, towhich a conduit 364 may be connected to direct exhausted air and steamaway from the manhole or other point of access to the “B” end of thesegment of conduit being repaired. As shown in FIG. 25, it is preferredto connect such a conduit to a suitable pressure regulating valve 374and to pressure and temperature gauges 370, 372 to monitor and controlthe curing process.

In many cases conduits being repaired include low spots such as at 398,where the intended or original continual downstream slope is no longerpresent, and fluids such as hot water and condensate from steam used toprovide the necessary heat for curing the tubular liner material tend toaccumulate undesirably. To remove such pooled water and to clean theliner and ensure that smooth flow is available through the repairedconduit, it is often desirable to force a clean-out pig 388 through therepaired conduit under the pressure of the heated air or other fluidutilized to cause the liner material to cure.

Suitable pigs are available commercially. For example, the YBS series ofpigs available from Girard Industries of Houston, Tex. are suitable.Such pigs are cylindrical or bullet-nosed cylindrical polyurethane foambodies which can easily be inserted into a tubular liner through theliner attachment hookup nozzle at the “A” end of a segment of conduitwhich has been repaired.

The “B” end fitting 376 shown in FIGS. 27 and 28 allows exhaust of airor an air and steam mixture from the far or “B” end of the conduit whilesuch a pig 388 is being propelled through the conduit. When the pigreaches the “B” end fitting 376 it continues to move past the exhaustport and is retained within the cavity 384 until curing is completed andthe fitting is removed from the newly installed liner 72.

Referring to FIGS. 25, 28, 29 and 30, in situations where it is notdesired to use a pressure retaining outlet fitting such as the “B” endfitting 376 shown in FIGS. 27 and 28, an exhaust port 400 may beinstalled in the liner itself as shown in FIGS. 29 and 30. The exhaustport 400, when installed, is generally planar so that a tubular linerincluding such an exhaust port can pass through an everter such as theeverter 16, allowing the tail end of the liner to remain closed after ithas been everted into the conduit being repaired, as shown in FIG. 25. Asoft plug or other type of knockout plug 402 is installed in such a port480, which is installed in a hole of appropriate size cut into the linermaterial 401 near the tail end. The port includes, in one embodiment, afirst flange 404 defining a tubular central portion equipped withthreads and a seat for a suitable knockout plug 402. The first flange404 is mounted on the side of the liner tube wall material that facesoutward before it is everted. That is, the first flange 404 is mountedon the polyurethane coated side of the felt liner tube wall. A backingflange 406 is located on the opposite side of the material. Flatheadbolts 408 or welded studs and T-nuts are used to hold the flangestogether in place in the liner. A sheet 410 of polyurethane may beattached to cover the first flange 404 and protect the polyurethanecoating of the portions of the liner 72 already in place, as the exhaustport 400 is carried along the length of a segment of conduit 179 beingrepaired.

Once the liner tube 72 has been everted in a conduit 179 the knockout402 or other plug is displaced and an exhaust fitting or valve manifold412 is installed in the port to permit adequate flow and maintainpressure within the liner tube during its curing. A portion 414 of theliner may be left intact with its end closed beyond the location of theport as shown in FIG. 25 and may be used to receive pigs 388 sentthrough the conduit. This may be particularly desirable in the processof repairing conduits whose diameter is larger than a few inches, wherea “B” end fitting 376 such as that shown in FIGS. 27 and 28 could becumbersome.

It will be understood that the direction in which the liner 72 iseverted into a section of a conduit 179 does not require that air andsteam or another fluid curing agent be installed from a particular endof the newly everted liner. Thus, the “A” end fitting 342 may beinstalled at the far end 368, distant from the everter 16. The “B” endfitting 376 or another connection to a suitable exhaust pressure controlvalve 374 and a drain valve 396 may then be located at the near end 92,where the everter 16 was used.

FIGS. 31 and 32 show a pinch-off tool 416 used to close off a section ofa liner 72 temporarily, as to permit installation of an end fitting.While primarily useful at the far or “B” end 368 of a newly evertedliner 72, such a tool might also be used at the near, or “A” end whilepreparing to disconnect the liner attachment hookup nozzle 344 from theeverter box 50 in preparation for connecting a pressure retaining “A”end fitting 342 to the hookup nozzle. The pinch-off tool 416 in apreferred embodiment is somewhat similar to a bumper jack for anautomobile, and includes a base in the form of a saddle 418 curved tofit against the cylindrical outer surface of a liner tube 72. The saddle418 has a choker hole 420 extending though it in line with a traveler422 mounted on a track 424 extending away from the base. The traveler422 is controllable by a suitable mechanism such as a lever-operatedratchet mechanism cooperating with the track 424, although othermechanisms such as hydraulic or pneumatic motors or screw arrangementscould also be used to move the traveler 422 along the track 424. Thetraveler includes an arm or hook 426 extending away from the track andextending above the choker hole 420 in the saddle 418. A strong flexibleelongate choker member 428, such as a rigging sling of synthetic fabricwith an eye 430 in each end, is attached to the hook or arm 426 of thetraveler, with a middle portion extending through the hole and forming aloop 432 beneath the saddle, within which the tubular liner 72 issqueezed or choked off tightly enough to maintain the required pressurewithin the liner 72 while the end of the liner is cut, a tail rope 182or lay flat hose is released, and a suitable fitting such as the “B” endfitting 376 shown in FIG. 28 is attached to the liner 72 and made readyfor use.

Referring next to FIGS. 33 and 34, when it is desired to keep theeverter apparatus 16 in place and attached to a flexible liner 72 duringthe curing process, a closure 434, shown in FIG. 33 installed on theeverter box 50, is used to close off the inlet slot 125 in the coverplate 122 more tightly than is accomplished by the lips of an inlet portused in pulling a liner 72 into the everter box 50. Once the tail end ofthe liner 72 has passed into the everter box 50, the closure 434 couldbe installed, even before the liner tube 72 has become fully evertedwithin the conduit 179 being repaired.

The closure 434 includes a metal plate 436 large enough to fully coverthe slot 125, and preferably has a gasket attached to its lower face.The gasket 438 may, for example, be made of felt of the same type usedin a wall of a liner 72, with a layer of polyurethane bonded to one sideof the felt. The polyurethane coated side of the felt preferably facesdownward to provide a tight seal against the upper surface of the coverplate 122 of the everter box 50.

A pair of bars 440 are welded to the top of the plate 436 and extendoutward on each side. The bars 440 include a bolt hole 442 at each end,to receive bolts to attach the curing closure 434 to the top of theeverter box 50 as shown in FIG. 33. The plate 436 defines a notch 444,seen in FIG. 33, and the gasket 438 includes a slit 446 extending infrom one side, aligned with the notch 444, so that the curing closure434 can be installed at once after the tail end of a liner 72 has passedinto the everter box 50, with the tail rope 182 continuing to pass intothe everter box 50 through the notch 444 and between the lips of thesealing port beneath the cover plate 122.

Using the apparatus of the invention just described it is possible toinstall and evert tubular liners to repair conduits quickly andinexpensively, without the need for such large equipment as thatdescribed in the prior art, Wood, U.S. Pat. No. 4,064,211.

As described above, most typical competitive pipe everting units eitheruse a column of water or a bladder to maintain pressure within theeverting apparatus. Such competitive everter apparatus are typicallylarge and bulky. Because everter apparatus 16 uses invented sealing port106, it is lighter and more compact than typical competitive everters

The invented everter apparatus can be less than 10 feet tall; somecompetitive everter apparatus are 30 feet tall. Competitive everters aretypically mounted on their own heavy duty vehicle, are too tall to passbeneath residential utility lines and often require a substantial amountof time to set up, including attaching guide wires to the tallapparatus. Because everter apparatus is so light and small, less than500 pounds, in another embodiment, without the frame 18, it issufficiently lightweight and sufficiently small that, with handles addedto it, it can be transported for a distance of at least 200 feet by twostrong workmen. The width of this embodiment of everter apparatus 16 isapproximately 22 inches without mounting sleeves 58 and 28 inches withmounting sleeves 58. One embodiment of everter apparatus 16 isapproximately nine feet tall. One embodiment of everter apparatus 16 ismounted on a mobile cart which can be attached to an ordinary pick-uptruck and delivered to the approximate pipe repair location and,thereafter, wheeled by two men through residential areas to the piperepair location.

An embodiment of everter apparatus 16 may be operated with compressedair supplying air from a one-inch, or less, air hose. One embodimentuses a ¾-inch air hose. Typical competitive everters often require alarge fire hydrant type water hose to fill the water column andunderground conduit and pipe liner and evert the liner. Everterapparatus 16 typically uses air to start the evertion process, andfollows the initial air with a compressed air and water nix. One method,for example, begins with air or water, or both; but, after the tail goesthrough the everter, uses an air chaser. Everter apparatus 16 requiresless water than do typical apparatus competitive everters. This ispossible with everter apparatus 16 because sealing port 106 is designedto permit slipping liner 72 through everter apparatus 16 without needingcolumns of water or bladders to hold the greater than ambient pressurewithin everter apparatus 16.

Everter apparatus 16 may usefully use air as its primary “fluid” drivingevertion of the liner 72. Using primarily air rather than primarilywater to operate everter apparatus 16 is a competitive advantage.Compressed air is accessible everywhere and air compressors are easierand quicker to provide and to set up than large water hoses used bytypical competitive everters to evert lines. Typical competitiveeverters often require a supply of water from a fire hydrant typemunicipal water supply within approximately 300 feet capable ofsupplying a 15 gallons per minute flow of water to the everter. Atypical garden hose blows at 15 gpm. A typical fire hose (200′×2½″)blows at more than 100 gpm. Everter apparatus 16, using compressed airfrom a transportable air compressor, may be used in areas remote frommunicipal water supplies. Because everter apparatus 16 uses less waterthan typical competitive everters, it causes less mud, mess, waterdamage, and water soaling at the pipe repair site.

Typical competitive everters are limited to starting and completingapproximately one job per day because it takes a substantial period oftime to bring typical competitive everter apparatus to the pipe repairlocation, set the everter apparatus up, attach water lines to asubstantial water source, evert the liner, then cure the liner in placein the pipe being repaired, pack the everter up, and clean up the messcaused by the large amount of water used.

As discussed above, smaller and lighter everter apparatus 16 can beeasily transported to the proximate pipe repair location and then moreeasily hand-wheeled on its wheels to the exact pipe repair location.Turning on the portable air compressor is quicker than connecting to asubstantial water supply. Once liner 72 is everted, everter apparatus 16can be more easily removed and transported to another pipe repairjobsite and replaced at the initial pipe repair site with a steam capand steam generator along with some air compressor as shown in FIG. 25for curing of liner 72. This permits the more valuable everter apparatus16 to be used on more than one pipe repair job in a day, sometimes asmany as three or four jobs in a work day. This is a substantialcompetitive advantage over typical competitive everters.

In one embodiment, the invented everter pipe repair system improves thepipe repair and liner sealant curing process by opening the end of liner72 at its “B” end, attaching a pressure release valve and temperatureand pressure gauges there and using the sane, in combination withappropriate steam, water, and air apparatus at the “A” end, tofacilitate and control a continuous flow through liner 72. For example,air compressor 360 may be run wide open, sending air into the “A” end ofliner 72 through liner 72 and out the “B” end of liner 72. The airpressure within liner 72 is controlled with a pressure gauge andpressure release valve at the “B” end of liner 72. A typical preferableair pressure in liner 72 as measured at its “B ” end is about 9 psi,although useful air pressures can be as high as 14 or as low as 5. Oncea continuous flow is established at an appropriate volume and pressurethrough liner 72, steam may be added to the flow through a pressure cap342, into liner 72's “A” end and circulated through liner 72 and outliner 72's “B” end. The exit temperature of the steam is measured by atemperature gauge 370 at liner 72's “B” end and regulated by regulatingeither the amount of steam entering at liner 72's “A” end or byregulating the amount of the steam and air mixture exiting at liner 72's“B” end via controlling the exiting volume and pressure valve at liner72's “B” end, or both. The steam temperature should be high enough toheat liner 72's thermosetting resins or other sealant sufficiently tocure it, but not so hot as to blister liner 72. A preferable temperaturefor the exiting steam is approximately 180–200 degrees Fahrenheit. Endfitting 376 shown in FIGS. 27 and 28 is not typically used incompetitive everting or curing operations. It speeds completion of piperepair jobs.

Some thermosetting resins cure with exothermic reactions. In this event,the air passing through liner 72 needs to remove heat from within liner72 and steam is not added; rather, liner 72 is air cooled by blowingcooling air or other fluid through liner 72. Many typical competitiverepair processes use hot water to cure the liner's thermosetting resinsor other sealant. The above described method of flowing air and steamthrough liner 72 is both more economical and produces better curingresults and requires less equipment and cleanup and capital and isquicker. Some resins are referred to as sealants.

An additional benefit of accessing the “B” end of liner 72 is that a pigmay be moved through liner 72 to squeegee out excess water orcondensate, from within liner 72 as shown in FIG. 27. The pig may bepropelled by pressure or pulled by a cable. This is useful becauseremoving accumulations of condensate, etc. in low spots, produces moreeven curing results. Typical everting operations cure the liner via areusable attachment leading from the everter to the “A” end of the pipe.The invented process instead cures liner 72 directly via the originalliner 72 extension from ground level to the “A” end of the pipe. Themethod of removing everting apparatus 16 at ground level and puttingsteam generator cap 342 on liner 72 at ground level has the effect of“wasting” that portion of liner 72 which extends from the immediate endof the pipe being everted up to ground level because, after liner 72 iscured in place within the pipe being repaired, the portion of liner 72extending from the end of the repaired pipe to ground level is cut offand thrown away. This cost is typically more than compensated for,however, by the time savings involved in quickly removing everterapparatus 16, replacing it with steam cap 342, and immediately beginningthe curing process using the installed liner rather than cutting liner72 off at the end of the pipe being repaired immediately after the lineris inserted and before the liner is cured. The time saved due to speedoutweighs the cost disadvantage of wasting of the liner material whichcannot be practicably reused.

Liner everter box 50, while preferably manufactured of aluminum plateswelded together for light weight may also be comprised of otherappropriate materials such as steel, reinforced plastic and the like. Inone embodiment, everting apparatus weighs less than 500 pounds, apreferred embodiment weighing approximately 350 pounds. The everterapparatus 16 shown in FIG. 1, with the exception of liner tube 72,tailrope 182 and lay-flat hose 186 weighs less than 400 pounds. Removingeverter box 50 from the frame substantially reduces its weight evenfurther permitting it to be carried into difficult pipe repairlocations.

Sealing port 106 is capable of being usefully used with more than oneparticular size of liner without being adjusted because its lips 112 and114 are adjustable. For example, a sealing port 106 sized to accept an8-inch liner 72, may also usefully accept a 6-inch liner 72. This helpsthe economics of invented everter apparatus 16 because it keeps everterapparatus 16 in the field and operating even if sequential repair jobsrequire differently sized liners 72 rather than the everter having to bereturned to a central location to have a new port attached to it foreach new repair job which requires a different size liner. Additionally,some liners are thicker than other liners and some sealants or resinsare easier to pull through the inlet port than others. Still further, inthe everter apparatus 16, the seals can be changed in the field if thecurrently installed seals are unable to accommodate a liner. In oneembodiment, adjustable inlet port nuts 330 as shown in FIG. 23 arepreferrably used to limit the travel of bars 314. Inlet port nuts 330are typically adjusted between everting jobs as needed. Adjusting inletport nuts 330 at the jobsite involves removing bolts and cover plate122, lifting and sliding lips 112 and 114 upon liner 72, accessing inletport nuts 330, adjusting inlet port nuts 330, and replacing cover plate122 and bolts. The adjustability of sealing port 106 and the ease inwhich seals can be changed out permits everter apparatus 16 to be usedwith liners of varying thickness and with resins and sealants of varyingviscosities without the necessity of taking everter apparatus 16 to acentral location to have sealing port 106 adjusted. This provides thebenefit of being able to more continuously keep everter apparatus 16 inthe field and working.

As show in FIG. 2, there is sufficient space within mounting sleeve 58to permit everter box 50 to be angled about upright support member 26 asdesired to any needed convenient angle for converter box 50 to meetprepared liner tube 72. This facilitates speedy installation and removalof everter apparatus 16 at the jobsite. Everter box 50 is light enoughthat it can be manually pushed into position to connect to prepared tubeliner 72. Then, when pressure is added to prepared tube 1 or 72, itstraightens as shown in FIG. 2. Everter box 50 can even be angledhorizontally for use in everting if necessary by making smallmodifications to mounting sleeve 58. The stiffness of liner 72 forceseverter apparatus 16 into the proper angle. The angle of everterapparatus 16 also may be adjusted at the jobsite by adjusting struts 32within support sleeves 34 and adjusting vertical support legs 40 withinmounting sleeves 42. This eliminates several alignment structures foundin typical competitive everters and speeds connection and removal ascompared to typical competitive everters and increases everter apparatus16 versatility in being able to fit in and adjust to the requirements ofdifficult jobsites better than typical competitive everters.

Mounting sleeve 58 is oversized relative to upright support member 26.Thus, when everter apparatus 16 is being transported, mounting sleeve 58can fit over upright support member 26. This results in a very short,vertical profile for everter apparatus 16 when it is being transported.This is particularly useful in areas that have overhead utility lines orother overhead structures.

In one embodiment, everter apparatus 16 measures less than ten feet fromthe top of upright support member 26 to the ground. Still, becauseeverter apparatus 16 is lightweight and small compared to typicalcompetitive everters, it can, when necessary, be removed entirely fromframe 18 and manually carried through passageways, up and downstaircases, etc., as may be necessary to reach difficult locations suchas a basement or other hard-to-access location. Everter apparatus 16 canbe disassembled into its component parts, moved to any location, andthen reassembled for use. Everter box 50 is less than five feet tall. Inanother embodiment, upright support member 26 is comprised of twoseparate vertical pieces, their attachment being a male/femalearrangement where the lower end of the upper part of upright supportmember 26 is a male attachment fitting within a female attachment of theupper end of the lower part of upright support member 26, or vice versa.

In one embodiment, everter apparatus 16 is swivelled forward duringtransportation at sleeve-like socket 28, which considerably shortens itsvertical height and makes it more stable while being moved. In thisembodiment, everter apparatus 16 is rotated vertically upward uponarriving at the site for positioning and use.

It is understood that “fluid” as used herein includes liquids, gases,and combinations of liquid and gas such as steam.

The terms and expressions which have been employed in the foregoingspecification are used therein as terms of description and not oflimitation, and there is no intention, in the use of such terms andexpressions, of excluding equivalents of the features shown anddescribed or portions thereof, it being recognized that the scope of theinvention is defined and limited only by the claims which follow.

1. In combination with a flexible tubular liner being installed toeffect repair of a conduit, a “B” end fitting comprising: (a) a bodyhaving an open circular first end aligned with and sealingly connectedwith an end of said tubular liner and a cylindrical cavity extendinginward from said first end toward a second end, said cavity having adiameter similar to an internal diameter of said tubular liner; (b) anexhaust port communicating with said cavity at least a predetermineddistance from said second end; (c) a drain port communicating with saidcavity; and (d) a respective valve associated with each of said ports,said valves being operable selectively to seal and to permit flow offluid from within said tubular liner.
 2. The combination of claim 1,including a pressure gauge connected with said “B” end fitting andoperatively located to sense fluid pressure within said tubular lineradjacent said “B” end thereof.
 3. The combination of claim 1, includinga temperature gauge operatively associated with said “B” end fitting andarranged to sense a temperature of fluid within said tubular lineradjacent said “B” end thereof.
 4. The combination of claim 1 wherein oneof said valves associated with said exhaust port is a pressureregulator.
 5. The combination of claim 1 wherein said drain port islocated at said second end.
 6. A flexible tubular liner for repair of aconduit, comprising: (a) a first end portion for installation at a nearend of a segment of a conduit to be repaired and from which said lineris extended by eversion inside said conduit; (b) an intermediate portionfor installation by eversion in said conduit to extend toward a far endof said segment; (c) a second end portion to extend from and beyond saidfar end of said segment, said second end portion including a connectordefining a port closed by a removable plug, said connector and said plugtogether being generally planar and being mounted in and orientedparallel with a wall of said second end portion.
 7. The tubular liner ofclaim 6 wherein said plug is a knockout plug arranged to be removed fromsaid port when said second end portion of said tubular liner extendsfrom said far end of said segment of conduit.
 8. A tool for temporarilyclosing off a flexible tubular liner and facilitating installation of anoutlet fitting, comprising: (a) a base including a saddle defining achoker hole therein; (b) a track; (c) a traveler mounted on said trackfor movement therealong; (d) a mechanism interconnecting said travelerand said track and operable to move said traveler along said track awayfrom said base; and (e) a length of strong flexible material attached tosaid traveler and extending through said choker hole as a loop beneathsaid saddle, said loop being decreased in size by said movement of saidtraveler away from said base.
 9. The tool of claim 8 wherein said lengthof strong flexible material includes an eye at each end, each of saideyes extending around a portion of said traveler.
 10. A method ofinstalling a liner in a hollow conduit, comprising: (a) everting aflexible liner tube impregnated with an uncured bonding andstrengthening material into said conduit through an everter from a firstaccess point to a second access point; (b) thereafter disconnecting saidflexible liner tube from said everter and interconnecting a pressureretaining inlet fitting with said flexible liner tube, in communicationwith an interior thereof, at a position in said flexible tube proximateone of said first and second access points; and (c) forcing a quantityof a fluid curing agent under a first pressure into the interior of saidflexible tube through said inlet fitting.
 11. The method of claim 10wherein said step of everting includes connecting a hookup nozzle tosaid flexible tube at a first end thereof and everting said flexibletube through said hookup nozzle, and wherein said step of installingsaid inlet fitting includes mating a pressure cap with said hookupnozzle.
 12. The method of claim 10, including providing a quantity ofsteam as a part of said fluid curing agent.
 13. The method of claim 12,including the step of controlling the temperature of said fluid curingagent within said flexible tube by regulating the amount of steamincluded in said fluid curing agent.
 14. The method of claim 10,including providing a quantity of hot water as apart of said fluidcuring agent.
 15. The method of claim 10, including providing a quantityof hot air as a part of said fluid curing agent.
 16. The method of claim10 wherein said step of everting includes the steps of connecting ahookup nozzle to said flexible tube at a first end thereof, andreleasably mating said hookup nozzle to an everter and thereaftereverting said flexible tube through said hookup nozzle; and wherein saidstep of installing said inlet fitting includes unmating said hookupnozzle from said everter and thereafter mating said hookup nozzle withsaid inlet fitting.
 17. The method of claim 10, including the furthersteps of installing a pressure retaining outlet fitting in said flexibletube in communication with said interior thereof adjacent the other ofsaid first and second access points; and establishing and regulating apredetermined second pressure within said flexible tube for apredetermined curing time, by releasing a controlled amount of saidfluid curing agent through said outlet fitting.
 18. The method of claim17 wherein said step of establishing and regulating said second pressureincludes operating a pressure regulating valve associated with saidoutlet fitting.
 19. The method of claim 17, including providing aquantity of steam as a part of said fluid curing agent and drainingcondensate from said liner through a condensate drain in said outletfitting.
 20. The method of claim 17, including the further steps OF: (a)introducing a pig into said liner through said hookup nozzle; (b)propelling said pig through said liner under pressure; and (c) catchingsaid pig in a pig receptacle portion of said outlet fitting. 21.Apparatus for use in everting a flexible tubular liner into the interiorof a hollow conduit, comprising: (a) a liner everter container having abottom having an out feed element defining out feed opening and having atop end including an inlet opening through which a liner can be fit intosaid liner everter container; (b) a liner inlet port assembly associatedwith said top end and defining said inlet opening in said top end, saidliner inlet port assembly comprising: (i) a pair of opposite endsinterconnecting said sides; (ii) an inlet mouth having a length and apair of opposite sides extending along said length; (iii) a pair offlexible lips interconnected with said mouth and located respectively onsaid opposite sides of said mouth and including respective exteriorsides and respective sealing surfaces facing toward each other, saidlips extending a first distance into said liner everter container towardsaid bottom, said distance being great enough for mutually confrontingportions of said sealing surfaces to be pressed sealing against eachother by fluid pressure within said liner everter container in excess ofambient atmospheric pressure surrounding said liner everter container;(c) said apparatus being designed and constructed to primarily usecompressed air to evert said liner and additionally comprising an aircompressor capable of supplying sufficient compressed air to saidapparatus to evert said liner within the hollow conduit said liner is torepair, said air compressor being in communication with said apparatus.22. The apparatus of claim 21 wherein said apparatus is designed andconstructed to weigh less than 500 pounds, to be capable of being movedthrough passages thirty-four inches wide, and to be capable of beingmoved under obstructions 13 feet high.
 23. The apparatus of claim 21additionally comprising a steam generator cap which, after removal ofsaid liner everter container from said liner, maybe placed incommunication with said liner and usefully used to generate andcommunicate sufficient steam into said liner to cure a sealant betweensaid liner and said hollow conduit, said steam cap not having a linerinlet.
 24. The apparatus of claim 21 additionally comprising an outletfitting capable of being attached to said liners “B” end, said outletfitting including a temperature gauge and a pressure gauge and apressure release valve, said outlet fitting, in combination with a steamgenerator in communication with said liner, being useful for permittingsteam to flow from said steam generator into said liner, through saidliner and out said outlet fitting, said temperature gauge, said pressuregauge and said pressure valve being capable of controlling thetemperature and the pressure of the fluid exiting from said outletfitting.
 25. The apparatus of claim 21 additionally comprising a steamcap capable of being substituted for said top of said liner evertercontainer after said liner has been everted into said pipe by saideverting apparatus, said steam cap being capable of communicatingsufficient steam into said liner to cure a sealant between said linerand said hollow conduit and said steam cap not having a liner inlet. 26.The apparatus of claim 21 additionally comprising a pig capable of beinginserted into the “A” end of said liner and moved through said linertoward the “B” end of said liner and removed from said “B” end of saidliner, movement of said pig through said liner being sufficient toremove substantially all condensate from the inside of said liner.
 27. Amethod of repairing a pipe by everting a liner within said pipe andsealing said everted pipe within said tube comprising: (a) transportingan everter apparatus to a pipe repair site; (b) inserting an end of saidliner into an inlet port of said everter apparatus, through said everterapparatus, out an outlet port of said everter apparatus and into saidpipe; (c) using an air compressor to generate compressed air;(d)communicating said compressed air to said everter apparatus; (e)using said compressed air within said everter apparatus to press a pairof lips located in said inlet port against said liner; (f) using saidcompressed air to evert said liner within said pipe to a predetermineddistance within said pipe; (g) flowing a fluid into said line to cure asealant between said liner and said pipe to seal said liner to saidpipe.
 28. The method of claim 27 additionally comprising putting a steamcap in communication with said liner, and using said steam cap to supplysufficient steam to within said liner to cure said sealant.
 29. Themethod of claim 27 additionally comprising using less than 5 gallons aminute of liquid during the process of everting said liner through saidpredetermined distance within said pipe.
 30. The method of claim 27additionally comprising using a vehicle to transport said everterapparatus to the general area of said pipe repair site, detaching saideverter apparatus from said vehicle, manually moving said everterapparatus to said pipe repair site and manually angling said everterapparatus to an angle appropriate for everting said liner to repair saidpipe.
 31. The method of claim 27 additionally comprising using onlywater which is transported to said pipe repair site for at least somedistance by means other than a conduit having a diameter of more thanone inch.